Unclear The exact wording that changed is not shown, so it is unclear how Claude's scheduling behaviour differs in practice.
CronCreate is the tool Claude uses to schedule a task to run later, either once or on a repeating timetable. The description that tells Claude how this tool works was rewritten in this release, in the main system prompt (the standing instructions Claude receives at the start of a conversation) for both the command line and the SDK.
The current description still covers these points:
- Scheduled jobs only run while Claude Code is idle, not in the middle of answering
- Durable jobs are saved to
.claude/scheduled_tasks.jsonand resume automatically the next time Claude Code starts - One-time durable tasks missed while Claude Code was closed are brought up for catch-up
- Session-only jobs end when Claude Code exits
- The scheduler shifts run times slightly: repeating tasks can fire up to 10% of their interval late (at most 15 minutes), and one-time tasks set for :00 or :30 can fire up to 90 seconds early
These instructions shape how Claude sets up scheduled tasks for you, such as which times it picks and whether it makes a job last across restarts, so a change in wording can change how it schedules things.
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
| [`$.tool.call`](/docs/en/plugins/mods/reference#mods-api-methods) of Bash with `run_in_background: true`, Monitor, or CronCreate | Resolves with `{ deny: '<tool> was not run: it starts background work, a schedule or a goal, and <reason>'…plugins/mods/api see the edit
* For a tool that [background subagents drop](/docs/en/sub-agents#available-tools), such as `CronCreate`, remove the entryerrors see the edit
The exact wording that changed is not shown, so it is unclear how Claude's scheduling behaviour differs in practice.
A small documentation edit on Error reference touched a line naming CronCreate after this was published.